Hello,
From your symptoms,it looks like eczema or dermatitis. It is a form of chronic dermatitis (rash).
Allergic reaction is one of the important causes of eczema. Allergic reaction can occur to strong soaps, Solvents, chemicals, certain foods, food additives, plants, metals, cosmetics, even urine and faeces of some animals (dust mites).
The groin itch that you are having can be due to jock itch or tinea cruris.It iis a fungal infection.